Freight railroad cars are critical to the economic well-being and global competitiveness of any industrialized country. For example, freight railroad cars move an estimated 42 percent of the United State's freight (measured in ton-miles) more than any other mode of transportation. Essentially all goods are shipped by rail—everything from lumber to vegetables, coal to orange juice, grain to automobiles, and chemicals to scrap iron. Freight carrying railcars connect businesses with each other across most countries and connect business within such countries with outside markets.
Rail provides major advantages in energy efficiency over other modes. On average, railroads are three times more fuel efficient than trucks. Railroads are environmentally friendly as the U.S. Environmental Protection Agency (EPA) estimates that for every ton-mile, a typical truck emits roughly three times more nitrogen oxides and particulates than a locomotive. Other studies suggest trucks emit six to 12 times more pollutants per ton-mile than do railroads, depending on the pollutant measured. Railroads also have a clear advantage in terms of greenhouse gas emissions. According to the Environmental Protection Agency (EPA), railroads account for just 9 percent of total transportation-related NOx emissions and 4 percent of transportation-related particulate emissions, even though they account for 42 percent of the nation's intercity freight ton-miles.
Further, freight railroads significantly alleviate highway congestion. A single intermodal train takes up to 280 trucks (equivalent to more than 1,100 cars) off associated highways; a train carrying other types of freight takes up to 500 trucks off the associated highways. It has been noted that overcrowded highways act as an “inefficiency tax” on our economy, seriously constraining economic growth. Freight railroads help relieve this restriction by reducing gridlock, enhancing mobility, and reducing the pressure to build costly new highways.
Finally, railroads have major safety advantages over other modes. For example, railroads are the safest way to transport hazardous materials. In the United States, railroads and trucks carry roughly equal hazrnat ton-mileage, but trucks have nearly 16 times more hazrnat releases than railroads. Thus there is a need to continue to improve and revitalize the freight car industry.
Focusing on improving the manufacturing process and car design and assembly can decrease associated costs and assembly time. It has been reported by the Highland Group that the implementation of lean manufacturing techniques and just in time inventory procedures to a railcar fabrication center was able to increase production at the facility of about 50%. This increase in efficiency can be further enhanced or supplemented with improved product design that attempt to maximize efficiency without altering railcar capacity or operation.
Coil cars are a specialized type of railcars, or rolling stock designed primarily for the transport of coils (i.e., rolls) of sheet metal, most commonly steel coils. For an overview of all freight car developments within the United States and associated industry trends see United States International Trade Commission 2011 report on Rolling Stock: Locomotives and Rail Cars (see http://www.usitc.gov/publications/332/ITS-08.pdf). Coil cars are often are considered a subtype of the gondola car, though coil cars bear little resemblance to a typical gondola. A gondola is generally an open-top type of rolling stock that is typically used for carrying loose bulk materials, while coil cars carry items such as plates or coils, or bulky items such as prefabricated pieces of rail track.
Prior to the development, and wide adoption, of coil cars, coils of sheet steel were carried on end or in cradles in open or covered gondolas. Load shifting, damage, and awkward loading and unloading were all problems with this type of loading, and since so much sheet steel is transported, a specialized car was designed for this use.
The body of a coil car consists of at least one trough, or a series of troughs, and may be lined with wood or other material to cushion the carried coils. The coils are set on their sides and supported by the sides forming the trough, and stops may be applied to keep the coils from shifting. Often the trough or pair of troughs are positioned longitudinal relative to the railcar as shown, for example, in U.S. Pat. Nos. 4,451,188 and 6,543,368, which are incorporated herein by reference.
The longitudinal placement of the troughs in a coil car can mean that the coils can be shifted in the trough due to the acceleration and deceleration and impact forces exerted due to the car motion along the track. Thus, in some instances, the coils are carried with their axes transverse to the direction of travel of the car. Representative examples of this construction include U.S. Pat. No. 1,850,597; U.S. Pat. No. 3,291,073 showing a coil skid design; U.S. Pat. No. 3,693,554 discloses a rail flat car with a plurality of transverse bulkheads; and U.S. Pat. No. 3,715,993 in which the cylindrical objects are cable reels. These patents are also incorporated herein by reference. Transverse coil cars typically have a number of parallel troughs, rather than one or two long trough(s). Each trough is generally V-shaped, and the coil sits in the transverse trough with the outer circumference of the coil tangent to the V at two points such that it cannot roll. The V-shaped troughs are generally lined, such as with wood decking to act as cushioning, thereby discouraging damage to the coils during loading or travel.
U.S. Pat. No. 2,810,602 discloses a trailer vehicle body which includes transverse laden supports and is also of general interest to the present invention.
FIG. 1 is a sectional side view of a conventional or prior art transverse coil car 10. This railcar 10 includes an open top body 12 on a pair of spaced trucks 14. As illustrated in this figures the body includes a center sill, pair of side sills, pair of top chords, a pair of side walls extending between each top chord and an associated side sill. The body in this example includes nine transverse troughs 16 that are each designed around a specific range of coils 18.
One difficulty with the illustrated construction of FIG. 1 is that a new car design must be developed essentially from scratch for changes in trough number or size. Traditionally traverse trough coil cars 10 are designed with a specific number of trough pockets 16 and each trough pocket configured to a particular minimum and maximum coil 18 diameter ranges. These troughs 16 on a coil car 10 often are configured with several different coil 18 diameter ranges often to maximize the efficiency of the associated design, and typically the resulting car 10 is associated with a specific custom design and results in many specialized parts for construction of the car 10. The design of the custom parts and fixtures adds to the design time and the fabrication time associated with the car design.
There remains a need in the industry to provide car designers with modular assemblies allowing new car designs to be easily implemented saving both design and manufacturing time and money.